Formation of hierarchical core-shell hollow Co3S4@NiCo2S4 nanocages with enhanced performance for supercapacitor

Metal-organic frameworks (MOFs) have sparked considerable interest as prospective metal precursors or sacrificial templates to design high-performance supercapacitor electrode materials. Here Co3S4@NiCo2S4 nanocages supercapacitor electrode material with a dual-core layer hollow structure was successfully constructed through an appropriate ion-exchange strategy of MOFs and the subsequent vulcanization treatment. The specific capacitance of the Co3S4@NiCo2S4 electrode was up to 1202 F g-1 at 1 A g-1 and could still attain 80% initial capacity at 10 A g-1. The integrated Co3S4@NiCo2S4//AC asymmetric supercapacitor achieved 58 Wh kg-1 of energy density at 750 W kg-1 of power density. The asymmetric supercapacitor retained 81.8% of its capacitance after 10,000 galvanostatic charge-discharge cycles. In this study, the in-dividual nanostructure and excellent electrochemical properties of Co3S4@NiCo2S4 nanocages provide a rational strategy for developing high-energy-density supercapacitor electrode materials based on MOFs derivatives.(c) 2023 Elsevier B.V. All rights reserved.